Truss tables for truss jigging and pressing systems are well known. Examples are disclosed in U.S. Pat. Nos. 4,943,038 (to Hamden), 5,085,414 (to Weaver), 5,702,095 (to Williams) and 5,553,375 (to Powers). In general, each of these references discloses an elongate truss table including a longitudinal series of table sections in which successive sections are separated by a respective transverse slot. Each table section includes a longitudinal series of transversely disposed relatively narrow panels with successive panels also separated by a respective transverse slot. Some slots, typically those between table sections, have a respective conveyor device able to be raised from a lower, retracted position to a position in which it is operable to move a substantially completed truss laterally off the table. Other slots house either fixed nuts or movable carriers to each of which a respective locator stop or puck is able to be secured on the top surface of the table, by means of a bolt. The stops are able to be secured in an array over the table surface, as required to enable them to accurately position lengths of timber which are to be secured in assembly to form a timber truss of a required configuration in which the timber lengths comprise chords and webs. The timber lengths are at least partially secured at junctions therebetween by toothed truss plates or nail plates which have been pressed to force teeth of each plate into each of the timber lengths forming a respective joint.
The truss or nail plates usually are partially pressed by a relatively light, travelling pressure roller which is passed over the truss table or by a platen press. The resultant partially completed truss then is moved off the table and pressing is completed by a heavier finishing roller. This double pressing procedure is used because the arrangement for securing the locator stops or pucks necessitates use of relatively wide slots between panels of the truss table. The width of the slots is such that if pressure sufficient to complete pressing on the table were to be used, the nail plates would not press satisfactorily or they would be deformed.
In addition to these constraints on pressing, the locator stops or pucks are such that considerable time is expended in securing them in required positions. Usually, each is secured by an Allen bolt tightened relative to a nut or carrier. This needs to be done carefully for each stop in turn to ensure that none of the stops is able to be inadvertently displaced during jigging and pressing.